This study explores No Child Left Behind's required timetable for English language learners (ELLs) to reach English language proficiency within five years, as outlined in the Annual Measurable Achievement Outcomes (AMAOs), despite the lack of research evidence to support this as a reasonable expectation. Analysis was conducted on the archived data from 1311 current and former Spanish-speaking ELLs, including students who qualify for Special Education (SpEd) and Talented and Gifted (TAG) programs. One-way chi-square analysis, contingency table analysis, relative frequency histograms, z-tests and t-tests were used to test hypotheses regarding statistically significant differences in TAG and SpEd identification rates and differences in acquisition timelines based on TAG or SpED classification, as well as instructional program model (bilingual versus English immersion). Results determined that Spanish-speaking ELLs were underidentified for TAG programs, despite extensive bilingual resources and staffing. Results further determine that ELLs as a whole require a mean 7.13 years to reach proficiency. Average ELLs without exceptionalities require 7.354 compared with 8.933 years for ELLs with disabilities (ELL-Ds), while TAG ELLs require 5.423 years, all longer than allowed by NCLB (five years) to reach proficiency. Significant differences were found in acquisition rates among TAG ELLs, ELL-Ds and average ELLs without exceptionalities. Analysis of timelines for ELLs in bilingual versus English immersion programs for ELLs as a whole, average ELLs and ELL-Ds with specific learning disabilities also found statistically significant differences, favoring bilingual programs. Overall, the results speak to the effectiveness of bilingual education program models for helping students to reach English proficiency and also to the need for consideration of additional factors in assessing schools based on AMAOs with five-year targets for language acquisition. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]